check

Is there some shell script file inside /boot directory that gets called on system startup? Alternatively, is there any way to make such a script run by modifying only files inside /boot (like some config setting)?

Thanks! That did the trick.

I'm trying to get to the point where I can read time from the DS3231 RTC module on a Raspberry Pi 4. From what I understand, I first need to activate i2c bus, then load the kernel module that would work with the clock itself. So far i2cdetect tool fails to detect anything. There are no i2c-* devices in /dev either. I've read about "Hardware" option in armbian-config, but it's not showing up in the menu. I've also read that it's a matter of adding a device tree overlay. Does that apply for RPI4? The folder structure in /boot seems different from what documentation and several threads describe for other boards. What would be the steps for activating i2c bus on RPI4?